Tool geometric parameters, which are key factors to be considered in tool design, have a direct effect on tool cutting performance. Based on the diversity and complexity of geometric parameters and technological goals, we select cutting force and temperature as initial input conditions to build a comprehensive dimensionless tool geometric parameters evaluation method. According to the multilevel weight relationships between the technological goals and the basic cutting characteristics, the evaluation factors for cutting force and temperature are determined. The comprehensive evaluation method (CEM) is then applied to analyze and optimize the key parameters of a saw milling tool. As shown by the research results, the parameters obtained by the CEM prove that some tool parameters from actual production were reasonable, while others had re-optimized space. The CEM is shown to be effective and feasible. Also, the analysis results have an explicit guiding function for production practice.